The letter must explain who is gifting the money, where the donor's funds are coming from and the relationship between the donor and the recipient. A gift letter for a mortgage shows your lender that you don't need to repay gift money toward your down payment.Use our mortgage gift letter A short letter like this sample gift letter will cover all of the requirements your lender needs. A gift letter is a note from a donor to your lender regarding cash funds for your mortgage down payment. Here's a sample gift letter you can use to prove that the money is truly meant as an outright gift, with no expectation of repayment. Use these stepbystep instructions for accepting a cash downpayment gift on a home, including a readytouse mortgage gift letter template.